Here’s the Shocking Link Between Daytime Sleepiness and Alzheimer’s

Scientists have long known that there’s a link between daytime sleepiness and dementia, but no one could say for certain which came first. Was this drowsiness a sign of cognitive decline? Or was it possible that drowsiness was actually causing it? While the former sounds more plausible, a groundbreaking study published on Monday in JAMA Neurology has found that, shockingly, the latter is actually true, at least when it comes to the elderly.

Researchers found that “excessive daytime sleepiness” in cognitively healthy people over 70 can lead to a buildup of a plaque in the brain called amyloid, which is considered the prime suspect in the onset of Alzheimer’s.

“In our study, we wanted to know if excessive daytime sleepiness causes an increase of amyloid over time in people without dementia,” study author Prashanthi Vemuri, a research faculty member at the Mayo Clinic, told CNN. “And the answer was yes.”

The results of the study were based on the brain scans and sleep questionnaires of 283 people, with an average age of 77, enrolled at the Mayo Clinic Study of Aging in Minnesota. Researchers studied the amount of amyloid buildup over the course of two years and compared that with how much daytime sleepiness was reported by participants. They had to be deemed free of dementia by specialists when the study began in order to participate. Those who experienced daytime drowsiness had far greater buildup, particularly in the areas of the brain associated with emotion and memory.

The study is likely to change not only the way doctors approach early signs of Alzheimers, but also how they emphasize the importance of sleep.

“Importantly, it is the first longitudinal study of the relationship between sleep and Alzheimer’s Disease in the preclinical stage, meaning before any cognitive changes appear,” Dr. Yo-El Ju, a neurologist at the Washington University School of Medicine, said. “This finding is important because it means we could potentially treat sleep problems to reduce risk of AD years down the road.”

According to the National Sleep Foundation, 20 percent of the population can be classified as having Excessive Sleepiness, which is defined as feeling drowsy or sluggish throughout the day. The most common cause of it is, as you might guess, poor sleeping habits.

Getting a good night of sleep is increasingly becoming recognized as one of the most crucial parts of a healthy lifestyle. In addition to causing dementia, not getting enough sleep can cause weight gain, memory loss, mood imbalance, high blood pressure, a weakened immune system, and low libido, not to mention increasing your risk of heart disease and diabetes.